A planter assembly adaptable to a pole or a wall. The assembly holds a large amount of water for passively watering plants therein at an optimized rate without over-saturating the potting soil. The assembly comprises a shell and a soil insert and a plurality of wicking units. The soil insert is removably nested within the shell. A plurality of wicking units are selectively attachable to the bottom of the soil insert. The wicking units are hollow so that soil from the soil insert falls therein to absorb water from the reservoir in the shell. The wicking units are designed to provide stable support without consuming water volume or adding unnecessarily to the overall weight of the assembly. Overflow ports prevent oversaturation of the potting soil. A bracket can be used to clamp the assembly to a pole. An optional iron cladding basket is available.